Initiation of DNA synthesis  DnaA tetramer binds to the OriC at the 9 bp repeat  This causes strand separation at this location ( AT rich 13bp repeat) due to supercoiling  DnaB gets delivered to location by DnaC, this binds to localized strand separation  DnaB has helicase activity which further unwinds the dsDNA  To prevent the strands from reanealing Single Stranded Binding (SSB) proteins come in and bind newly separated strands  Primase( DnaG) primes the reaction and gyrase relieves strain

An overview of DNA replication  Now strands are separated Primase creates a short RNA primer  Once the replication fork is opened, DNA pol III comes in and begins replication -tethered to DnaB  Leading strand synthesis is continuous  Lagging strand starts the same way, but a primase needs to prime EACH okazaki fragment, replisome dissociates and move to next Beta clamp  DNA must be looped out to synthesize strands together  DNA pol I removes RNA primer, ligase ligates fragments together

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